Photographic print developing unit

ABSTRACT

A photographic print developing unit comprising a housing including a cover and opposed walls for supporting a rotatable canister for developing photographic prints. The housing defines a compartment within which is placed a heater. The housing supports beakers containing the liquid chemistry to be used during the development process. The processing liquids are sequentially introduced into the canister while in a substantially vertical orientation and maintained out of contact with the print by a fluid guide element until the canister is placed in a horizontal orientation. The canister and the beakers are preheated and thereafter maintained at a uniform temperature during the development process.

United States Patent Primary Examiner-Samuel S. Matthews Assistant Examiner-Fred L. Braun Attorney-Denny & Denny ABSTRACT: A photographic print developing unit comprising a housing including a cover and opposed walls for supporting a rotatable canister for developing photographic prints. The housing defines a compartment within which is placed a heater. The housing supports beakers containing the liquid chemistry to be used during the development process. The processing liquids are sequentially introduced into the canister while in a substantially vertical orientation and maintained out of contact with the print by a fluid guide element until the canister is placed in a horizontal orientation. The canister and the beakers are preheated and thereafter maintained at a uniform temperature during the development process.

Patented Dec. 14, 1971 2 Sheets-Sheet 1 Patented Dec. 14, 1971 2 Sheets-Sheet 2 SEBASTIAN SPERANZA PHOTOGRAPIIIC PRINT DEVELOPING UNIT BACKGROUND OF THE INVENTION This invention relates to a photographic processing unit and especially a unit for the development or processing of color photographic prints and, in particular, to a unit for the processing of coated, flat sheets of photographic material for producing color photographic prints.

In the processing of color printing papers, the necessity for accurately establishing and controlling the processing temperatures, for accurately timing the processing steps, and for maintaining the proper relationships between the processing liquids and the photographic paper undergoing the processing is appreciated throughout the industry. Although these considerations are important in the processing of black and white photographic materials, they become critical in the processing of color photographic materials to achieve best results.

An object of my invention is to provide a unit which requires a minimum amount of liquid chemistry for the complete processing of even large prints, thereby making economical the use of fresh liquid chemistry for each print, and which makes the discarding of the liquid chemistry after a single use economically feasible.

A further object is to reduce the handling of the print during processing and for this reason I provide a canister within which the exposed photographic material is placed and never again handled until completion of the processing at which time it is taken out and dried.

It is still further object to provide a unit in which the temperature is automatically regulated and maintained at the desired level with little or no attention by the operator once it is established, unlike existing water controlled systems.

In my unit, since I provide an enclosed canister, and since surface area is minimized by the small amount of liquid chemistry needed, noxious fumes from the liquid chemistry (especially at higher temperature) are substantiallj reduced, reducing the health hazard from deep breathing of these fumes from large amounts of exposed liquid chemistry, as in previous systems using trays.

Further, as compared to a system using trays, the likelihood I of accidental spillage is considerably reduced, if not eliminated, as is also the possible contamination of successive liquids by carryover from one to another, or by careless handling of trays.

l have also found that the life of the reserve liquid chemistry is substantially increased, since my method is based on a use as needed philosophy. That is, substantial oxidation occurs when a large amount of the liquid chemistry is left exposed to air over a long period of time. The life of the liquid is considerably shortened by this oxidation, especially the liquid developers. In my process, the chemistry is discarded immediately after use, since only small portions are needed per print (for example, 2 ounces per one 8 inch l inch print).

BRIEF SUMMARY OF THE INVENTION ment.

I provide for the establishment and maintenance of the required processing temperature for all of the liquids required during the processing, throughout the processing cycle, including the liquid being used during the development of a particular print, by the same electrical device, because the housing defines a completely dry air chamber that surrounds the necessary liquids required in the process, both prior to and during use thereof.

My unit may be made small, light weight and portable, one embodiment measures about 12 inch l4 inch l4 inch, making it suitable for a maximum size print of 8 inchXlO inch. It can be used anywhere once the print has been loaded into the canister and the liquid chemistry is in the beakers. It needs no special darkroom equipment and operates on normal l l0 volt house current.

Another feature of my invention is the provision of a processing canister which encloses the material that is being processed so that processing may be conducted in normal room illumination after the processing has been initiated in a dark room.

A further feature of the processing canister is the introduction of guide means, such as parallel guide rails, to direct the flow of the liquids during pouring thereof into the canister, thereby assuring that the liquid will not contact the print unevenly and nonuniforrnly.

Still another feature of my invention is the provision of stop means located in the canister to limit the placement of the printing paper during initial insertion thereof, so as to hold the paper spaced from the liquid chemistry until processing begins.

Another feature is the provision of a means for rotational agitation of the canister to assure an even and equal distribution of the liquid over the surface of the photographic material or print during processing.

The foregoing and other objects of this invention, the principles of this invention, and the best modes in which I have contemplated applying such principles will more fully appear from the following description and accompanying drawings in illustration thereof.

BRIEF DESCRIPTION OF THE VIEWS In the drawings:

FIG. 1 is a perspective view illustrating the improved photographic print developing unit of my invention;

FIG. 2 is a cross-sectional view taken along the line 2-2 in FIG. 1;

FIG. 3 is an end view of the canister showing the coverspout through which liquid is poured into the canister;

FIG. 4 is an enlarged longitudinal, cross-sectional view of the canister forming part of the photographic print developing unit;

FIG. 5 is an inside, end view of the canister cover-spout;

FIG. 6 is a cross-sectional view taken along the line 6-6 in FIG. 4; and

FIG. 7 is a diagrammatic view illustrating the approximate position of the canister while liquid is poured into it.

DETAILED DESCRIPTION Referring to the drawings in detail, FIG. 1 illustrates a photographic print developing unit 10 constructed in accordance with my invention comprising a housing or box 12 defining an enclosed air compartment 14. The housing 12 supports a developing can or canister 16 and beakers 18 for suitable chemicals, i.e., liquid chemistry, used in photographic print processing.

The housing 12 comprises a bottom wall 20, opposed front and backwalls 21 and 22 opposed sidewalls 23 and 24, and a cover 28. The upper portions of the walls 21, 22, 23 and 24 may be provided with integral inwardly extending tabs 31, 32, 33 and 34 upon which rest the marginal portions of the cover 28, as shown, and to which the cover is secured by suitable screws 35. The leftmost tabs 31 and 32 are spaced from the wall 33, as shown, to permit a U-shaped section 40 of the cover 28 to extend downward. toward the bottom wall 20, so as to provide a U-shaped well 42 having a semicircular bottom shape, as shown in FIG. 2. The U-shaped section 40 is preferably spaced from the sidewall 23 and the bottom wall 28, as shown, and extends completely between the opposed front and backwalls 21 and 22, so that a U-shaped zone of heated air surrounds the well 42 along its entire length. Also, the well 42 is deep enough to receive substantially all of the canister 16, as shown by the dot-dash position of the canister in FIG. 2.

Mounted upon the bottom wall and within the compartment 14 is an electrical sheathed heater 44 which may be connected by a cord 46 to a suitable electrical source and suitably insulated from the housing 12. The heater 44 is connected to a thermostatic control 48 mounted on the front wall 21 with a portion extending into the compartment 14. The thermostatic control 48 is used to energize and deenergize the heater 44 so as to properly regulate the heat produced thereby so as to preheat the liquid chemistry and the canister and thereafter to maintain them at the proper temperature.

The cover 28 has two rows each with four holes 50 formed therein to receive a corresponding number of the beakers 18, although the number thereof may vary. The beakers 18 extend through the holes 50 into the compartment 14 and are generally cylindrical, but have outwardly enlarged truncated parts 52, whereby the beakers 18 are supported on the cover 28 so that the liquid containing parts of the beakers are well within the compartment 14 while portions of the beakers are outside the compartment and above the cover 28. The portions of the beakers 18 above the cover are easily grasped manually when the beakers are to be removed from the housmg.

The canister 16 comprises an open ended cylindrical portion 70 closed at the left end by a cap 72 and closed at the right end by a removable cover-spout 74, FIG. 3. The removable cover-spout 74 comprises a cap 76 and an inner baffle 78,

the cap 76 and baffle 78 being spaced from each other and having zigzag interfitting shapes, in cross section, as shown in FIG. 4, so as to define a channel 80 through which liquids may enter or leave the canister but through which light may not pass. The cap 76 and baffle 80 are concentrically secured to each other in spaced relation by rivetlike bushings 82. The channel 80 is in communication with a spout-spindle 84 through which liquids may be placed into the canister. The spout 84 is a cylindrical member suitably secured to the cap 76 and having its rightmost end 86 cut diagonally for ease in pouring liquid into and out of the canister.

Secured to the left end 72 is a cylindrical spindle 88, similar to the spindle forming the spout-spindle 84, the spindle 88 and the spout-spindle 84 being concentric with the cylindrical portion 70 of the canister.

The well 42 is long enough, i.e., the space between the opposed front and back walls 21 and 22 at the well 42, to accommodate the part of the canister between the caps 72 and 74, as shown in FIG. 1. Further, the wall 40 defining the well 42 has a semicircular shape, in cross section, at its bottom conforming to the diameter of the cylindrical portion 70 of the canister 16, and the well 42 is deep enough to receive substantially all of the cylindrical portion 70 of the canister. Thus, a U-shaped zone is formed, within the compartment 14, around the well 42 to transfer heat uniformly to the wall 40 which in turn transfers heat to the cylindrical portion 70.

The cylindrical portion 70 is supported for rotating on the bottom curved part of the wall 40 while the spindle 88 and the spout-spindle 84 extend through aligned U-shaped open ended slots 21 and 22 which together define the ends of the front and backwalls 21 and 22 which together define the ends of the well 42. The spindle 88 and the spout-spindle 84 provide convenient handles by which the canister 16 may be manually grasped and rotated.

Secured to the inside of the cylindrical portion 70 is a guide rail 100 having an elongated, U-shape defining a channel 101. The photographic material, i.e., the photographic paper, after it is exposed, is formed into a tubelike shape 102 and placed within the canister, under dark room conditions, with the emulsion side facing radially inwardly and with its longitudinal edges spaced from each other on opposite sides of the spaced legs 103 and 104 of the guide rail 100.

The cylindrical portion 70 of the canister is made longer than the longest print to be developed so as to accommodate, in the space or reservoir 110, all of the liquid chemistry to be used in each step processing of the print while the canister is held at a few degrees from its horizontal position, FIG. 7. To

prevent movement of the print into the space or reservoir 110 radial stop pins 106 are suitably secured to the cylindrical portion 70, as shown in FIGS. 4 and 6.

Suitable markings, such as the arrows shown in FIG. 1, are placed on the cap 76 and the adjacent edge of the cylindrical portion 70 to circumferentially align the spout end 86 relative to the guide rail so that when the canister is tipped upwardly a few degrees from the horizontal, see FIG. 7, and liquid is poured into the spout 84, with the spout end 86 now substantially horizontal, it will flow into the canister down the channel 101 of the guide rail 100 to the bottom space or reservoir 110 at the left end of the canister.

As illustrated, the guide rail 100 preferably extends passed the print 102 a short distance so as to insure that all of the liquid will be initially guided passed the print. To further insure that no liquid prematurely contacts any of the print, the guide rail could be inverted, relative to the position shown in FIG. 6, so as to define, with a part of the cylindrical wall of the canister, a tube open at opposite ends.

The guide rail 100 may be secured to the cylindrical portion 70 by any suitable means, such as by being soldered thereto.

Preferably, the cap 72 is secured to the cylindrical portion 70 by being soldered thereto, as is the spindle 88 to the cap 72.

The cap 76 and the adjacent end of the cylindrical portion 70 may be provided with suitable threads so that the cap 76 may be threaded onto it or a friction fit between the two may be provided.

Also, while not illustrated, the guide rail 100 could be secured to the cover-spout 74 and not to the cylindrical portion 70.

Further, while also no illustrated, the guide rail 100 could be replaced by a tube (not shown) substantially concentric with the cover-spout 74 and in fluid communication the spout thereof, the tube being long enough to carry liquid to the bottom space or reservoir 110 of the canister.

The spindle 88 and the spout-spindle 84 extend outwardly of the back and front walls 22 and 21, respectively, as shown, and provide convenient means by which the canister may be manually rotated, although a motor-driven means, not shown, could also be provided. I

The mating cylindrical faces of the cylindrical portion 70 of the canister and the semicircular canister supporting part of the wall 40 extend along the length of the well 42 to provide for uniform and rapid heat transfer from the heated compartment 14 to the canister 16. Likewise, the liquids within the beakers are quickly and uniformly heated, since the beakers 18 extend for almost their entire length into the compartment 14.

The housing 12 has been made of a suitable sheet material, such as, stainless steel, bent to suitable shape. The beakers 18 and the canister 16 have also been made of stainless steel. However, other materials, such as a polyvinylchloride (PVC) plastic or epoxy coated metals could be substituted for the stainless steel. It is required, of course, that the material be resistant to the liquids being used in the development process, but the preferred material is one of the high heat conductivity, such as metal, particularly for the canister.

The method of using the photographic print development unit 10 of my invention is to connect the heater 44 by the cord 46 to a suitable electrical source. The liquid chemistry is poured into the beakers 16 after the unit has preheated, preferably, to the required temperature.

Under dark room conditions, the photographically exposed print 102 is loaded into the canister 16 and the cover-spout 74 is replaced.

Suitable illumination of the room may then be resumed at which time the cover-spout 74 may be rotated, if need be, so as to bring the bottom of the spout-spindle 84 into proper fluid alignment with the guide rail 100.

The canister 16 is then tilted, to the approximate position shown in FIG. 7 and the initial developer poured into the canister through the spout end 86, the liquid flowing from the bottom of the cover-spout 74 into the channel 101 without touching the photographic paper 102 at this time, as the legs 103 and 104 keep the liquid from contacting the paper. Thus, the liquid, a relatively small amount, relative to the amount within the canister, flows into the space or reservoir 110, at the left-hand end of the canister 16, FIG. 7', to the left or the leftmost edge of the paper 102.

After all the required liquid is poured into the canister 16 it is placed within the well, in the horizontal position shown in FIGS. 1 and 2, at which time the liquid spreads horizontally and evenly to cover the paper 102, but over a small arcuate part only, as shown in FIGS. 4 and 6. The canister 16 is now rotated back and forth for the amount of time required during which time the paper passes uniformly through the liquid. The eccentric rail 100 helps make the rotation easier and steadier, as its eccentricity introduces a flywheel effect tending to always return the canister to its initial position.

At the end of the required development period of the liquid is poured out by tilting the canister downwardly. Thereafter, the second liquid is introduced into the canister in the same manner as the first liquid and the canister again supported in the well 42 and agitated by rotation for the required time period.

Liquids are placed within the canister and removed therefrom successively, until the print is treated with the required liquids. When the print is to be washed with water, the spout-spindle 84 may be held under a spigot or the coverspout 74 removed entirely.

If the process requires a second light exposure the coverspout 74 is removed and the large, open end of the canister is rotated near a light source. This causes the print to be exposed to a light source without requiring manual contact therewith. After the second exposure to light, the development process is completed by treating the photographic paper with the required chemicals.

lf desired, the support surface of the U-shaped section 40 may be treated with a friction reducing coating such as Teflon i.e., tetrafluoroethylene, or the exterior cylindrical surface of the canister 16 may be so treated, or friction-reducing bearings could be provided.

Also, the canister could be preformed with an integral channel similar to the channel 101, but such preformed canister is not shown.

It will be understood that while the cover-spout 74 is constructed so that the liquid chemistry flows into and out of the canister, through the spout-spindle 84 and channel 80, the dimensions of the cap 76 are such that when the canister 16 is substantially horizontal enough liquid lies within the canister to evenly cover an arcuate portion of the photographic material 102 along its entire length without spilling out the channel 80 and spout-spindle 84.

In the preferred form, when the beakers 18 are in place, as shown in FIGS. 1 and 2, the housing 12 is entirely closed on its six sides, as shown, to completely enclose the compartment 14, so as to facilitate heating thereof and minimizing spillage of liquids into the compartment 14. Further, in the preferred form, the canister 16 is restrained from endwise movement by the portions of the front and backwalls 21 and 22 which form the slots 90 and 91, although the length of the well 42 is slightly longer than the distance between the caps 72 and 76 so as to facilitate easy rotation and agitation of the canister 16.

Having described this invention, what I claim is:

1. A photographic print developing unit comprising a housing including a cover and opposed walls,

a developing can supported by said housing for rotation thereon, said housing defining a compartment, a heater within said compartment, and beakers, said housing including means to rotatably support said can, said heater being mounted within said compartment so as to heat the air within said compartment,

said can having a cylindrical shape, said cover surrounding said compartment and having holes through which said beakers extend so as to minimize accidental entry of liquids into said compartment and substantially close said holes said housing including wall portions limiting movement of said can along its longitudinal axis,

said can having spindles extending through said wall portions for rotation thereof, said support means for said can extending into said compartment, and

said support means conforming at least in part to the exterior cylindrical shape of said can so as to provide for easy rotation of said can and so as to provide for good heat conduction between said housing and said can.

2. The developing unit recited in claim 1 wherein beakers extend through said holes into said compartment and are supported by said cover so that portions of said beakers are disposed above said cover.

3. The developing unit recited in claim 1 wherein said spindles extend out beyond said wall portions whereby said can may be manually rotated.

4. The developing unit recited in claim 3 wherein said means supports said tank so that more than one-half of said can is disposed below said cover.

5. The developing unit recited in claim I wherein said support means extends into said compartment, said can includes lighttight means for pouring liquid into said can without contacting the photographic material within the can until said can is held substantially horizontally.

6. The developing unit recited in claim 5 wherein said support means is semicircular and provides a heat conductive transfer means to rapidly transfer heat from said compartment to said can.

7. For use in photographic development process, a canister to receive photographically exposed material, said canister comprising a longitudinal, tubular wall and end wall inlet means for the flow of liquid into said tubular wall without contacting said material, said end wall inlet means being lighttight, and said tubular wall also having axially extending guide means within said canister for receiving said liquid without contacting said material, said canister also defining a reservoir at the end opposite said end wall inlet means, and said guide means being in communication with said end wall inlet means and said reservoir.

8. The canister recited in claim 7 wherein said end wall inlet means has an angular opening for ease in pouring liquid into and out of said canister, said tubular wall and end wall inlet means being provided with suitable indicia to align said end wall inlet means relative to said guide means so that when said angular opening is in approximately a horizontal plane the liquid poured into said end wall inlet means will flow directly into said guide means without contacting said material.

9. The canister recited in claim 8 wherein said canister includes stop means to limit placement of said material into said canister. 

1. A photographic print developing unit comprising a housing including a cover and opposed walls, a developing can supported by said housing for rotation thereon, said housing defining a compartment, a heater within said compartment, and beakers, said housing including means to rotatably support said can, said heater being mounted within said compartment so as to heat the air within said compartment, said can having a cylindrical shape, said cover surrounding said compartment and having holes through which said beakers extend so as to minimize accidental entry of liquids into said compartment and substantially close said holes, said housing including wall portions limiting movement of said can along its longitudinal axis, said can having spindles extending through said wall portions for rotation thereof, said support means for said can extending into said compartment, and said support means conforming at least in part to the exterior cylindrical shape of said can so as to provide for easy rotation of said can and so as to provide for good heat conduction between said housing and said can.
 2. The developing unit recited in claim 1 wherein beakers extend through said holes into said compartment and are supported by said cover so that portions of said beakers are disposed above said cover.
 3. The developing unit recited in claim 1 wherein said spindles extend out beyond said wall portions whereby said can may be manually rotated.
 4. The developing unit recited in claim 3 wherein said means supports said tank so that more than one-half of said can is disposed below said cover.
 5. The developing unit recited in claim 1 wherein said support means extends into said compartment, said can includes lighttight means for pouring liquid into said can without contacting the photographic material within the can until said can is held substantially horizontally.
 6. The developing unit recited in claim 5 wherein said support means is semicircular and provides a heat conductive transfer means to rapidly transfer heat from said compartment to said can.
 7. For use in a photographic development process, a canister to receive photographically exposed material, said canister comprising a longitudinal, tubular wall and end wall inlet means for the flow of liquid into said tubular wall without contacting said material, said end wall inlet means being lighttight, and said tubular wall also having axially extending guide means within said canister for receiving said liquid without contacting said material, said canister also defining a reservoir at the end opposite said end wall inlet means, and said guide means being in communication with said end wall inlet means and said reservoir.
 8. The canister recited in claim 7 wherein said end wall inlet means has an angular opening for ease in pouring liquid into and out of said canister, said tubular wall and end wall inlet means being provided with suitable indicia to align said end wall inlet means relative to said guide means so that when said angular opEning is in approximately a horizontal plane the liquid poured into said end wall inlet means will flow directly into said guide means without contacting said material.
 9. The canister recited in claim 8 wherein said canister includes stop means to limit placement of said material into said canister. 